The present invention relates to a switchgear and more particularly, to a switchgear which uses an insulation arc-extinguishing medium such as SF6 gas and the arrangement of respective apparatuses of which is improved.
In recent years, in order to effectively supply power to large city areas, such tendency becomes strong that power systems of high voltage are directly introduced into overpopulated streets and underground, and according to this tendency, gas-insulated switchgears have come to be installed to secure an insulation distance and to minimize the installation spaces for equipment.
The gas-insulated switchgear is constructed by connecting a plurality of gas-insulated apparatuses, each of which contains conducting portions in a grounded tank filled with a gas which is excellent in insulation arc-extinguishing performance such as SF6 gas. Since the gas-insulated switchgear is excellent in reliability and reducibility of the installation place, use thereof is being extended to large city areas as a demand for power in the large city areas becomes large in amount and high in density.
A conventional gas-insulated switchgear is formed as follows. That is, a receiving side branch bus container which contains therein a bus electrically connected to a circuit breaker through a current transformer (CT) is connected to a lower portion of a circuit breaker container which contains therein the circuit breaker together with SF6 gas excellent in insulation gas-extinguishing performance, and the bus inside the receiving side branch bus container is connected to a receiving side power cable contained in a receiving side power cable container through a disconnecting switch contained in a disconnecting switch container and led out of the switchgear.
On the other hand, a transmission side branch bus container which contains therein a bus electrically connected to the circuit breaker through another current transformer (CT) is connected to an upper portion of the circuit breaker container on the opposite side to the side on which the above-mentioned receiving side branch bus container is located. The bus inside the transmission side branch bus container is connected to a receiving side power cable contained in a transmission side power cable container and led out of the switchgear. Those apparatus are arranged in an about straight line.
This kind of gas-insulated switchgear is disclosed in JP A 10-285728.
In the above-mentioned conventional construction, the receiving side branch bus container and the transmission side branch bus container extend from upper and lower portions of the circuit breaker container in the opposite direction, respectively, so that it is inevitable that the size in the length direction L becomes large, and as a result, the installation area becomes large. Further, since the receiving side branch bus container and the transmission side branch bus container extend from the upper and lower portions of the circuit breaker container in the opposite direction, respectively, surplus spaces are formed above the receiving side branch bus container and below the transmission side branch bus container and it has a lot of useless spaces.
The present invention is made in view of the above-mentioned matters and an object of the present invention is to provide a switchgear which is less in useless space and of which an installation area can be reduced.
The present invention to attain the above object resides in a switchgear which is characterized in that a connecting portion to be connected to a transmission side branch bus container and a connecting portion to be connected to a receiving side branch bus container are provided on a circuit breaker container in an up and down relation so as to face the same direction, any one of the transmission side branch bus container and the receiving side branch bus container is connected to the connecting portion positioned on the upper side, and the other is connected to the connecting portion positioned on the lower side, and a transmission side power cable terminal container or a receiving side power cable terminal container is arranged at a position deviated horizontally from the axis of the transmission side branch bus container or the receiving side branch bus container; or in that a connecting portion to be connected to a transmission side branch bus container and a connecting portion to be connected to a receiving side branch bus container are provided on a circuit breaker container in an up and down relation so as to face the same direction, the receiving side branch bus container is connected to the connecting portion positioned on the upper side, and the transmission side branch bus container is connected to the connecting portion positioned on the lower side, and a transmission side power cable terminal container and a receiving side power cable terminal container are arranged so as to oppose each other at positions deviated horizontally from the axes of the transmission side branch bus container and the receiving side branch bus container.